Carburetor structure



Sept. 6, 1960 w. c. EBERLINE CARBURETOR STRUCTURE 2 Sheets$heet 2Original Filed May 18, 1955 F10. 6 LJ IN VEN TOR.

WILL/AM CHARLES EBERLINE XWM KM A TTORNEVS.

P atented Sept. 6, 1960 CARBURETOR STRUCTURE.

3 Claims. 01. 261-71) This invention relates to a carburetor for use oninternal combustion engines.

This application is a division of my co-pendingapplication, Serial No.509,154, filed May 18, 1955.

The invention may be applied to various types of carburetors and isespecially adapted to carburetors for relatively small utility enginessuch as those used on lawn mowers, small farm and gardening equipment,pumps and the like. a l

I An object of the invention is to provide a generally improved, simple,inexpensive bowl structure-and an improved structure for controlling thefiow of fuel from the bowl for mixing with air.

Generally the invention contemplates a bowl having spaced apart deep andshallow regions with an improved drain cock in the deep region and thefuel outlet positioried at the shallow region for improved separation offoreign matter from the fuel. 'A float controlling the' fuel inlet valveis provided with stop means, preventing it from striking againstadjacent parts of the carburetor in order to prolong the life of thefloat. The mixture control valve is provided with exterior operatingmeans selectively operable to make fine and general mixture adjustments.One form of the invention isshown in the accompanying drawings:

Figure 1, is a side elevational view of a carburetor ac cording to thisinvention.

FigureZ, is an enlarged sectional view on line 22 of Figure 1. j Figure3 is a sectional view on line 3-3of Figure 2 illustrating the drain cockstructure.

[Figure 4 is an enlarged generally sectional view on line 44 of Figure1.

Figure 5 is an enlarged, fragmentary, top elevational view illustratinga detent structure for controlling the choke.

Figure 6 is an enlarged generally sectional view on line 6-6 of Figure1, illustrating the mixture control means with some parts shown inphantom.

T he carburetor shown in the drawings has abody 10 with an air inlet 11,a venturi' 12, and a mixture outlet 13 adapted to be secured to the fuelinlet of an internal combustion engine (not shown). A valve member 14 ininlet 11 provides a choke and another valve member 15 adajacent themixture outlet provides a throttle. The

adjacent opening 27 and a seal element 32 is preferably interposedbetween body 10 and top of bowl 25 (Figure 1).

Bowl 25 defines a chamber 35 containing a torus shaped float 36 havingone side portion 37 connected to a hinge 38 rotatably secured to body 10through a pivot 39. Float 36 preferably comprisesa hollow shell formedof thin corrosion resisting metal of the order of .004 to .007 inchthick. Body 10 has a fuel inlet passageway 40 adapted to receive a fuelline 41 and communicating into chamber 35 through an orifice 42 and apassageway 43. A valve member 45 slidable' in passageway 43-has a sealelement 46 for opening and closing orifice 42 and has a lower endportion 47 supported by an element 48 on hinge 38.

Hinge 38 has a projection 49 which engages a projection 50 on the bodywhen float 36 is in a downward.

position for a purpose to be described. Chamber 35is vented as by a port53 in body 10 and a manually op erable valve 54 is provided for cuttingoff the fuel supply to orifice 42. Valve 54 has a seal member 55 biaseddownwardly as Figure 1 is viewed by spring 56 and has an operatinghandle 57.

Bowl 25 is fashioned so that its deepest portion 60 is generallyadjacent its periphery and so that its central region 61 is relativelyshallow (Figure l). Mixture control means for the carburetor includes apassageway 62 constricted as at 63 to form an orifice opening intopassageway 18 and a taper valve member 64 projecting choke and throttleare controlled respectively by exterior through the orifice. Passageway62 has an intake branch 65 communicating into the shallow centralportion of bowl 25 through a port 66. Another branch 67 of passageway 62communicates into the idling jet passageway 19.

Valve member 64 has an elongate shank 70 projecting through hollow bolt26 and outwardly of bowl 25. Shank 70 has a threaded connection to apacking gland 71 which is in turn threaded to the interior of bolt 26 asat 72 and which secures packing 73 in place. The outer end of shank 70is enlarged to form a head 74 which may be turned for advancing andretracting taper valve element 64 for adjusting the size of orifice 63.

A wrench member or lever member 76 is operably connected to head 74 andis detachable therefrom. For this purpose head 74 preferably has anon-circular shape such as the hexagonal shape shown and lever 76 haslugs or projections 77 positioned to engage the sides 780i the head.Shank 70 projects through an opening 79 in the lever member so that thelever is shiftable axially of the shank for selectively engaging anddisengaging the lugs and the side faces of head74. A compressed coilspring 80 seating on the lever member and on bowl 25 or washer 30adjacent thereto biases lugs 77 into engaged relation with head 74.

provided on the edge portion of body 10 (Figs. 1 and 4'):

i The graduations may be numbered as shown in Figure 1 and may compriseindentations as shown in Figure 4 for a detent engagement with aprojection 84 on lever 76. The lever may be provided with a projection85 forming a finger hold for convenient operation.

A drain opening 87 is provided in the deepest portion of bowl.25 and theportions of the bowl defining the open-,

ing arepeened or extruded outwardly 'to form an annular shoulder 88(Fig. 1). A valve member 89 projects through opening 87 and has a sealmember 90 forclosing the opening. Valve member 89 has ahead 91 .at'itsouter end and a compressed coil spring 92' seats on the head 91 andaround shoulder 88 on bowl 25 to: bias the valve toward closed position.Shoulder 88 engages the Tend convolution of spring 92 as shown in FigureZfoi securing the spring in a generally axially extending positionrelatively to valve member 89.

Choke lever 16 has a generally circular inner portion 95 providedwithrecesses 96, and a small coil spring 97 is attached 'to body andpositioned to engage within a recess 96 when in unstressed conditionSpring 97 and recesses 96 cooperate to form a detent for positioningchoke lever 16 and valve 14 thereon at predetermined positions.

. In handling and shipment of the carburetor prior to its use' on anengine, bowl 25 is empty and float 36 is unsupported except by hinge 38.The float is thus free to swing downwardly as Figure 2 is viewed to theposition illustrated in dotted lines. Projection 49 on the hinge engagesprojection 50 on body 10 to form a stop limiting the downward movementof the float. The float is thus held in a position spaced from the bowl,thereby minimizing damage to the relatively thin metal of the floatfromcontact with adjacent parts during handling and shipment.

As to operation of the carburetor, it may be assumed that mixture outlet13 is connected to the fuel intake of an internal combustion engine (notshown) and that valve 54 is in the open position shown in Figure 2 withoperating handle 57 horizontal and seal member 55 elevated. Drainopening 87 is closed by seal element 90. Gasoline entering chamber 35from fuel .line 41 through passageway 40, orifice 42 and passageway 45has filled the chamber to the level shown in broken lines 98 in Figure 2and float 36 has swung upwardly on hinge 38 to the solid line position,raising element 48 and valve member 45 to close orifice 42.

. When the engine connected to mixture outlet 13 is in operation, air isdrawn in through inlet 11, passes through venturi 12, and draws raw fuelfrom chamber 35 through passageway 18, orifice 63, passageway 65 andport 66. The fuel and air are intermixed and pass into the engine frommixture outlet 13. The amount of raw fuel entering the air streamthrough passageway 18 is regulated by turning head 74 to advance orretract valve member 64 for adjusting the size of the orifice at 63.

To obtain a rough or general adjustment of orifice 63, lever 76 isshifted upwardly as Figure 2 is viewed against the action of spring 80to disengage lugs 77 from head 74 so that the head and valve member maybe freely manually turned. When the desired adjustment has been made,lever 76 is released and shifts downwardly under the action of spring 80so that lugs 77 re-engage head '74. Fine mixture adjustments may then beconveniently made by manually shifting the easily accessible upperportion of lever 76 to selective alignment with the graduations ordetents 83 on carburetor body 10. Lugs 77 engage sides 78 of head 74 inthe manner of a wrench for turning the valve member as lever 76 isshifted. Projection 85 provides a finger hold for shifting lever 76.Subsequent adjustments for leaving or enriching the fuel mixture may bemade from time to time by turning lever 76 or by shifting the leverupwardly and turning head 74 directly.

Over a period of time foreign matter separates from the fuel in therelatively large quiescent zone provided by chamber 35 in bowl 25. Theheavier foreign matter such as water and sediment collects in thedeeper, generally peripheral region 60 of the bowl. Port 66 of intakebranch 65 lies adjacent the shallow central region of chamber 35 and isthus removed from the sediment collecting region 60 of the chamber sothat fuel entering branch 65 for ultimate mixture with air at venturi 12is largely free of foreign matter.

Drain opening 87 is located in the deep peripheral portion of the bowlto insure complete drainage of the cup when opened. Outwardly extrudedannular shoulder 88 adjacent the drain opening provides means forpositively positioning the contiguous convolution of spring 92 so thatthe spring is secured in a generally co-axial position relatively tovalve member 89. The spring thus urges valve member 89 straightdownwardly as Figure 2 is viewed to seat seal member 90 evenly andsecurely over drain opening 87 to provide an effective and reliableseal.

From time to time float chamber 36 may be emptied such as for enginemaintenance or draining bowl 25 and float 36 will hinge downwardly tothe dotted line position shown in Figure 2. Projection 49 on the hingethen engages projection 50 on body 10 to hold the iioat in a positionspaced from the bowl, thereby minimizing damage to the float asdescribed above.

What is claimed is as follows:

1. A carburetor comprising, a body, said body having fuel inlet meansand air inlet means, said body having mixture control means for mixingfuel and air therein and having mixture outlet means adapted to beconnected to the fuel intake of an engine, said mixture control meansincluding a passageway for fuel connecting into said air intake means,and means forming'a valve member, said valve member having a threadedconnection to said body and being operable rotatably to regulate theflowof fuel through said passageway, said valve member having aportionprojecting outwardly of said body, said outwardly projecting portionhaving an enlarged portion positioned for direct manual manipulation,whereby to regulate generally the flow of fuel in said passageway, saidenlarged portion having an out of round shape, lever means 'con-.

nected to said outwardly extending portion of said valve member, saidlever means having lug means mating with said out of round enlargedportion, means forming arcuately arranged graduations on the exterior ofsaid body, said lever means being shiftable to selective alignment withsaid graduations, whereby to finely regulate the flow of fuel throughsaid passageway, said lug means being detachable from said out of roundenlarged portion.

to facilitate free rotation of the latter, whereby selectively toregulate such flow of fuel generally and finely,1 and means to bias saidlug means against said enlarged portion and simultaneously to hold saidlever means in contact with said serrations.

2. A carburetor comprising, a body, said body having fuel inlet meansand air inlet means, said body having mixture control means for mixingfuel and air therein and having mixture outlet means adapted to beconnected to the fuel intake of an engine, said mixture control meansincluding a passageway for fuel connecting into said air intake means,and means forming :a valve member, said valve member having a threadedconnection to said body and being operable rotatably to regulate the,flow of fuel through said passageway, said valve memmeans overlying andencircling said projecting portion and mating with said out of roundenlarged portion, means forming arcuately arranged graduations on theexterior of said body, said lever means being shiftable to selectlvealignment with said graduations, whereby to finely regulate the flow offuel through said passageway, said lever means being shiftable axiallyof said outwardly projecting portion of said valve member for detachingsaid lug means from said enlarged portion, to facilitate free rotationof the latter, whereby selectively to regulate such flow of fuelgenerally and finely, and spring means seating on said body and on saidthe lug portion of said lever means, said spring means being stressed toyieldably hold one end of said lever means in operative engagement withsaid enlarged portion and to hold the f other end of said lever means inyieldable contact with said arcuately arranged graduations.

3. In a carburetor of the type having a body with fuel inlet means andair inlet means, said body having mixture control means for mixing fueland air therein and having mixture outlet means adapted to be connectedto the fuel intake of an engine, said mixture control means including apassageway for fuel connecting into said air intake means, and valvemeans operable to regulate the flow of fuel through said passageway,that improvement which comprises an operating member on said valve meansprojecting outwardly of said body and being positioned for directoperating manipulation, whereby to regulate generally the flow of fuelin said passageway, an acircular head on the projecting end of saidoperating member, a manual control lever having a mounting endencircling said projecting portion of said operating member and engagingsaid 'acircular head in separable engagement therewith, an extension onsaid operating lever projecting toward said body shaped to engage spacedserrations in said body selectively, and spring means to hold saidencircling portion on and against said head portion and to bias theextending portion of said lever into engagement with said serrations on.said body in various positions of adjustment, said spring permittingrelative axial motion of said encircling portion of said lever to permitrotative adjustment between said lever and said operating member andpermitting motion of said extending portion of said lever away from saidbody to permit adjustment of said operating member by said lever tovarious positions defined by said serrations.

References Cited in the file of this patent UNITED STATES PATENTS1,196,976 Pembroke Sept. 5, 1916 1,328,590 Royce Jan. 20, 1920 1,394,687Reid Oct. 25, 1921 1,475,404 Newman Nov. 27, 1923

